The present invention relates generally to tomosynthesis imaging. More specifically, the invention relates to cross table tomosynthesis in a trauma application.
Tomography involves obtaining a two-dimensional image slice (or tomogram) from a three-dimensional volume. A variety of tomographic imaging techniques exist today, such as conventional linear tomography, computed axial tomography (CT), and positron emission tomography (PET).
A relatively new and promising tomographic imaging technique is tomosynthesis. Tomosynthesis allows retrospective reconstruction of an arbitrary number of tomographic planes of anatomies from a set of projection images acquired over a variety of angles. Compared to conventional linear tomography, tomosynthesis provides premium image quality and enhanced depth information at a lower x-ray dose. Image quality and depth information is, of course, important when diagnosing patients. Additionally, tomosynthesis is relatively fast and cost-effective.
For trauma patients such as accident victims, it is critical to rapidly localize the site and extent of the injury for successful treatment and rehabilitation. As victims are often unconscious, imaging of vertebra misalignment (for example, lateral view) is often required for a patient at a supine position. Conventional x-ray systems are usually present in hospital emergency rooms, and these systems can provide fast, high resolution imaging of the patient spine.
However, such systems often fail to provide views through thick parts of a patient anatomy (for example, a shoulder) or to differentiate between overlapping bony structures (for example, a skull). In addition, such systems may not localize the site of the injury in three dimensions.
CT systems have been used as a potential solution to the above problems in trauma cases. However, these systems have several shortcomings. First, these systems are not typically found in emergency rooms. Therefore, additional time is required to move a patient to a CT system. In addition, CT scanning is usually slow compared to x-ray imaging. In emergency situations, this additional time may not be available.
CT systems also typically have larger spatial resolution than an x-ray image for an image plane that is perpendicular to the x-ray direction due to re-slicing, for example. Moreover, the x-ray dose from a CT imaging system is usually much higher than for an x-ray system. For example, CT imaging systems may use doses up to 10 times or more than doses used in x-ray systems.
Thus, a need exists for an x-ray system and method that provides for fast, high resolution imaging of a patient anatomy (such as a spine or other body parts), along with three-dimensional localization of a patient injury and good contrast resolution. In addition, the above needs should be met with existing equipment found in emergency rooms. These needs may be met using digital x-ray tomosynthesis systems and methods described herein.